package test26;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: ws
 * Date: 2023-04-19
 * Time: 10:46
 */
//https://www.nowcoder.com/practice/953b74ca5c4d44bb91f39ac4ddea0fee?tpId=230&tqId=39750&ru=/exam/oj
import java.util.*;

// 公式推导，在题解中
public class Main1 {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int a = in.nextInt();
        a--;
        System.out.println(1 << a);
    }
}
